Extracted stay points:
laltitude	longitude	arriving time	leaving time
40.00642767647059 116.32535211764703 2009-04-03,04:09:51 2009-04-03,05:16:15
39.99976229090908 116.32724843636363 2009-04-03,06:00:35 2009-04-03,07:46:45
40.0097318597786 116.31520604797055 2009-04-03,10:27:25 2009-04-03,11:07:15
40.00969968333076 116.3151558194295 2009-04-03,12:50:20 2009-04-04,03:35:55
39.989371843971696 116.27226123404256 2009-04-04,07:47:29 2009-04-04,08:21:14
39.90892432442752 116.40539420229005 2009-04-04,11:22:44 2009-04-04,12:03:24
40.009774692913396 116.31510699999993 2009-04-04,14:03:14 2009-04-04,14:35:09
